UK and European Allies Must Prepare to Defend Europe Without US Support, MPs Warn
A powerful parliamentary committee has issued a stark warning that the United Kingdom and its NATO allies in Europe must urgently prepare for a "worst-case scenario" where the United States may not come to their defence during a crisis. The Joint Committee on the National Security Strategy, composed of influential peers and MPs, emphasized that the increasing unpredictability of White House security priorities is fundamentally challenging long-standing NATO assumptions about European defence.
Unpredictable US Priorities Undermine NATO Foundations
The committee's report, published on Friday 27 March 2026, highlights how European defence strategy has always been built around the fundamental belief that American armed forces would serve as the dominant power supporting allies in any conflict. This assumption is now being upended by what the committee describes as the "increased unpredictability" of Washington's security priorities under the Trump administration.
The intervention comes as President Trump has repeatedly criticized NATO allies, particularly targeting the United Kingdom for choosing not to join his war against Iran. In recent social media posts, the president mocked the Royal Navy's aircraft carriers as "toys" and accused fellow NATO countries of having "done absolutely nothing" to help combat the Iranian regime.
Critical Security Dependencies at Risk
The committee identified several critical areas where UK national security could be compromised by tensions between the Trump administration and Sir Keir Starmer's government. These vulnerabilities include:
- Maintenance of Trident missiles used in the navy's nuclear deterrent submarines
- Intelligence sharing arrangements with American agencies
- Access to advanced military programmes such as the F-35 jet
- Collaboration on new attack submarine development plans
The report specifically warned that "there are demonstrable areas of tension in the UK-US relationship that may compromise the reliability of these dependencies in the near future." It further cautioned about the potential for President Trump to leverage these dependencies against allies who take actions he disapproves of.
Urgent Call for European Strategic Independence
The committee urged London to develop a clear plan to "move away from a bilateral relationship with the United States that is so dependent on the latter for nuclear and intelligence operations, and conventional defence." This represents a significant shift from decades of security partnership built around the so-called "special relationship" between the two nations.
The parliamentary committee advised the UK, Europe and Canada to develop a comprehensive strategy "for a transition towards greater European leadership of NATO." This recommendation acknowledges that a European-only military force would currently be substantially less capable than one supported by American resources, given that the US military provides critical elements including satellite intelligence, electronic warfare capabilities, and overwhelming mass in any conflict.
Historical Context and Future Implications
The Supreme Allied Commander Europe position has only ever been held by an American officer since NATO's founding, symbolizing the alliance's historical dependence on US leadership. The committee's warning suggests this arrangement may no longer be sustainable given current political realities.
Britain finds itself particularly exposed to any weakening of transatlantic bonds due to its exceptionally close security and defence partnership with the United States, developed over many decades. The committee emphasized that while the government should continue collaborating with the US where practical, it must simultaneously work with European partners to invest in independent capabilities that could offset a potential American withdrawal from European defence commitments.
The report concluded with a sobering assessment: "Preparing for a 'worst-case scenario' whereby Europe can no longer rely on US support in the event of a crisis, the Government must work with European partners to invest in its own capabilities to offset this potential withdrawal." This represents one of the most significant reassessments of UK and European security strategy in recent memory.
